Panel advises FDA to approve lorcaserin obesity pill

(CBS/AP) A panel of expert advisers to the Food and Drug Administration recommended late Thursday that they approve sales of what would be the first new prescription weight-loss drug in the U.S. in more than a decade, despite some concerns over heart risks.

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The panel voted 18-4 with one abstention to recommend approval of Arena's lorcaserin, concluding that its benefits "outweigh the potential risks when used long term" in overweight and obese people.

"We will continue to work with the FDA as the agency completes its review," Arena CEO Jack Lief said in a statement.

The drug is intended for people who are obese or for people who are overweight and have at least one weight-related health problem, such as high blood pressure.

Arena said the FDA has set a target date of June 27 for deciding whether to approve sales of the drug. The FDA is not bound to follow the advice of its advisory panels, but it often does.

Lorcaserin is one of three experimental weight-loss drugs whose developers have been trying for a second time to win approval, after the FDA shot them all down in 2010 or early 2011 because of serious potential side effects.

Earlier this year, rival Vivus Inc. won endorsement from an FDA panel for its diet drug Qnexa after previously being rejected due to safety concerns, HealthPopreported. That move raised expectations for both Arena and Orexigen Therapeutics Inc., the third company racing to get the first new diet drug into drugstores.

The panel's vote Thursday comes two days after federal health regulators gave a surprisingly favorable assessment of lorcaserin. When the agency turned the drug down in 2010, its scientists raised concerns about health issues such as tumors that developed in laboratory animals tested with the drug. In the interim, the San Diego company again applied for approval, submitting additional data in hopes of swaying the agency to a favorable decision.

A review of all the research studies by FDA staff, posted online Tuesday, stated that new analysis Arena submitted suggests there's only a "negligible risk" of tumors in people taking the drug. However, questions remain about it possibly increasing risk of high blood pressure in diabetics or damaging heart valves, a life-threatening side effect that has been an issue with some earlier weight-loss pills.

If the FDA agrees with the panel's recommendation, lorcaserin could be the first obesity pill of the trio to hit the market. A month ago, Vivus said that the FDA had pushed back its target date for a final decision on Qnexa from April 17 until July 17. The agency said it needed more time to consider a new drug safety plan submitted by the company.

While patients and doctors are eager for new obesity treatments, the pills are far from magic weight loss remedies. Research showed that people taking lorcaserin had modest weight loss, on average losing just 3.1 percent of starting body weight over a year. More than 37 percent of patients lost 5 percent of their weight or more, which is enough to meet FDA standards for effectiveness. By comparison, average weight loss with Qnexa was 11 percent, with more than 83 percent of patients losing 5 percent of their weight or more.

Currently, the only drug approved for long-term weight loss in the U.S. is orlistat, which is sold as the prescription drug Xenical and over the counter as alli. The drug works by blocking the absorption of fat, but hasn't gained traction because of unpleasant side effects, including loose bowel movements.

The quest for a safe weight loss pill has been filled with bumps along the way, HealthPopreported. In the 1950s and '60s, amphetamines were used for weight loss but the pills were highly addictive and dangerously increased blood pressure and heart rate. In the 1990's, a combination drug called fen-phen (fenfluramine) was recalled because one-third of people taking it experienced heart valve damage, resulting in more than a $13 billion settlement of tens and thousands of personal injury lawsuits.